Long-Term Monitoring and Prediction for Settlement and Composition of Refuse in Shanghai Laogang Municipal Landfill

Parameters about composition of refuse such as mass percentage of biodegradable matter, volatile solid, organic carbon, cellulose, total sugar, and settlement were monitored and analyzed in a large-scale experimental unit. The empirical formulas between composition and refuse age were established in terms of the data obtained from the experimental unit and verified by comparing with the corresponding parameters of refuse in the closed landfill units from 1991 until 1994 in the Shanghai Laogang Municipal Landfill. Furthermore, the long-term prediction for the composition of refuse was made, and it was predicted that the half-life is 7 to 11 years for biodegradable matter, 9 to 12 years for organic carbon or volatile solid, 7 to 16 years for cellulose, and 4 to 6 years for total sugar. In addition, a mathematical model, based on the mechanism of refuse biodegradation in the landfill, was developed to simulate the relationship between the settlement and the refuse age and manifests the secondary settlement potential. The mathematical model was proved not only to be reliable but also should be accurate for predicting the settlement of the landfill. The secondary settlement, which mainly results from the slow and gradual biodegradation of refuse, is linear with respect to the exponent of refuse age. Finally, according to the settlement model and empirical biodegradation formulas, it may be predicted that, 79.4% of biodegradable matter, 92.9% of total sugar, 72.7% of volatile solid and organic carbon, and 73.1% of cellulose will be biodegraded and that 79% of the maximum secondary settlement potential will occur before the Shanghai Laogang Municipal Landfill is in a high stabilization situation, i.e., approximately 21 years after final closure.     

Sustainable use of stormwater for irrigation case study: Manly Golf Course

Sustainability has become an increasingly used term, but what does it mean in terms of practice. This research will look at the harvesting of captured stormwater for the irrigation of urban playing fields and what the implications are for catchment hydrology, local community, and local council. This research aims to identify, understand and determine the catchment conditions that may hinder the stormwater quality and quantity for capture and reuse, as well as determining whether the stormwater harvesting will be sustainable. Research methods for this project will include systemic analysis in order to further investigate the assumptions being made in the study. Manly Golf Club has relied on groundwater extraction supplemented by potable supplies for irrigation, however potable supplies are no longer available. It has been proposed to provide irrigation supplies from stormwater via onsite storage and groundwater recharge. Monitored stormwater entering the Golf Course from the adjacent Cemetery Creek sub-catchment for pollutants, have indicated that it may be suitable for irrigation with treatment and may reduce problems generated by overuse of groundwater. The proposal will provide environmental benefit through reduced pollution loads being discharged directly to receiving waters and cessation of use of potable supplies by the Club. Social and economic benefits are expected to be gained and will be monitored as part of an ongoing research program.     

中国工业废水处理过程CDM项目机会研究

文章通过对联合国环境署制订的用于工业废水处理项目中实施清洁发展机制（CDM）合格性识别的方法学进行分析,以及根据项目建议书和官方网站信息统计归纳的国外工业废水处理项目CDM开发的成功案例,并结合中国工业废水氧化塘处理法的现状情况,对中国工业废水尤其是高浓度有机废水处理中CDM项目开发机会进行了探索性的研究,提出在食品工业尤其是酒精废水、淀粉废水、酿酒废水的处理过程中开展CDM项目的可行性。以此对中国工业废水中CDM项目的未来开发情况进行了设想与建议。     

哈尔滨垃圾堆场内渗滤液的降解行为模拟试验研究

通过对哈尔滨城市生活垃圾的堆放方式进行模拟试验,研究了垃圾堆场内渗滤液的降解行为,并预测出哈尔滨以及在寒冷气候条件下的东北地区渗滤液COD、BOD5和NH3-N浓度达到稳定化至少需要11年.     

氮磷在塘-湿地组合生态系统中的去除机制研究

采用多种形式的塘和湿地组合生态工艺完善传统的生态塘和湿地系统,能实现系统处理环境的多样化,提升对氮、磷的去除效能。对山东某组合生态处理系统的研究表明,组合生态处理系统能够有效提升对氮、磷营养物的去除效果。各生态单元水环境的差异影响着氮和磷的主导去除机制,使氮、磷表现出不同的季节去除规律。其中氮的去除主要依靠生物的硝化反硝化作用。底泥中的磷按照Fe-P>OPalk>Al-P>Ca-P>OPres逐渐变为Ca-P>Fe-P>Al-P>OPalk>OPres,与磷共沉降逐渐成为的主导去除机制。     

Treatment and remediation of a wastewater lagoon using microelectrolysis and modified DAT/IAT methods

To examine treatment and remediation of a wastewater lagoon with poor biodegradability, a typical wastewater lagoon in Tianjin, China, was treated and remedied using microelectrolysis and modified demand aeration tank (DAT)/intermittent aeration tank (IAT) methods. After pretreatment by microelectrolysis, the removal e ciency of chemical oxygen demand (COD) was up to 64.6% and the ratio of BOC/COD in the e uent increased from 0.013 to 0.609. The removal rates of CODCr and NH+4 -N were a ected by sludge backflow rate, mixed liquor suspended solids (MLSS), and hydraulic retention time (HRT) in the modified DAT/IAT reactor. The highest removal rates of CODCr and NH+4 -N were up to 78.9% and 62.6%, respectively, when the sludge backflow rate was 38.0 mL/min, the total HRT was 8.0 hr and MLSS was 4088.0 mg/L. In this case, some protozoa and metazoa were observed in activated sludge and biofilm carriers. Most of chrominance was removed by microelectrolysis treatment, while the modified DAT/IAT methods were more e ective for CODCr and NH+4 -N removal.     

Dioxins in the Venice lagoon

Venice is famous around the world for its uniqueness and architectural splendours, arts and the history of the “Serenissima Repubblica”, as it was known in the past, but few are aware that Venice economy is strongly dependent on the industrial activities based mainly on the adjacent Porto Marghera area. For many years, the lagoon that physically separates the city from the dry land has avoided association between the concern connected with the pollution derived from these industrial activities and the public perception of Venice. Since 1995, dioxins have appeared as a lagoon contaminant, and their presence, at such a level requiring immediate “in depth” studies and interventions, has been fully realized for decades.     

An integrated river basin-coast-sea modelling scenario for nitrogen management in coastal waters

Linked river basin and coastal water models were applied to analyse the effects of an optimal nitrogen management scenario in the Oder/Odra river basin on water quality in the Oder (Szczecin) Lagoon and the Pomeranian Bay (Baltic Sea). This scenario would reduce nitrogen loads into the coastal waters by about 35%, a level which is similar to the load of the late 1960’s. During summer the primary production and algae biomass in the Oder estuary is limited by nitrogen, which makes a nitrogen management reasonable. The comparison of the late 1960’s and the mid 1990’s shows that an optimal nitrogen management has positive effects on coastal water quality and algae biomass. However, this realistic nitrogen reduction scenario would not ensure a good coastal water quality according to the European Water Framework Directive. A good water quality in the river will not be sufficient to ensure a good water quality in the lagoon. Nitrogen load reductions bear the risk of increased potentially toxic, blue-green algae blooms, especially in the Baltic coastal sea. However, to reach water quality improvements in lagoons and inner coastal waters, nitrogen cuts are necessary. A mere focus on phosphorus is not sufficient.     

Spatio-Temporal Fluxes in Particulate Organic Carbon in a Tropical Coastal Lagoon

Temporal and spatial variations in particulate organic carbon (POC) in relation to primary production, chlorophyll a, phaeophytin, plankton abundance, secondary production and suspended particulate matter (SPM) were studied monthly for 1 year from April 1996 to March 1997 in a shallow tropical coastal lagoon on the southwest coast of India. Though temporal variations in all components were significant, spatial variabilities were not statistically significant. POC values range from 200 to 5690 mg C m³ h⁻¹, while primary production, chlorophyll a, and phaeophytin varied between 0.02 and 14.53 mg C m⁻³ h⁻¹, 0.87 and 23.11 mg m⁻³ and 3.02 and 30.581 mg m⁻³, respectively. Phytoplankton and zooplankton abundance varied from 0.01 to 655.5×10⁵ no m⁻³ and negligible to 7.08×10⁵ no m⁻³ respectively; secondary production from 10 to 490 mg C m⁻³ and SPM between 0.38 and 74.43×10⁴ mg m⁻³ during this study. Temporally, postmonsoon months were observed to have the highest concentrations of POC in the lagoon waters. The bulk of the POC pool in the lagoon was composed of secondary producers (72%), followed by chlorophyll a (21%), phaeophytin (7%) and suspended particulate matter of inorganic origin (< 0.1%).     

Survey of Levels of Phthalate Ester Plasticizers in a Sewage Lagoon Effluent and a Receiving Stream

In this study, samples from a sewage treatment lagoon and those from a receiving stream were analyzed for their phthalate esters content. Knowledge of the distribution of ubiquitous phthalate esters in the sewage lagoon and the receiving stream was necessary because of the reports of their subtle toxicity to aquatic biota and humans. Liquid–liquid extraction, Clean-up experiment and High Performance Liquid Chromatography (HPLC) were the methods employed for the quantitative determination of the Phthalates. A study of uncontaminated water was done to establish blank levels. The sewage lagoon and the receiving stream were grossly polluted as several phthalate ester plasticizers: DMP, DEP, DPhP, DBP, DEHP, DOP and DINP were found present at monthly mean levels of between 24.02 mg/L and 139.25 mg/L in the sewage treatment lagoon and 10.41 mg/L and 80.53 mg/L in the receiving stream. The results showed higher levels of phthalate esters in the sewage lagoon compared to the receiving stream. The sewage lagoon was identified as a pollution point source into the receiving stream. Levels of phthalates obtained from the receiving stream are much higher than the water criteria of 3 μg/L phthalates recommended by the United States Environmental Protection Agency (USEPA) for the protection of fish and other aquatic life in water and the Suggested No-Adverse Effect Levels (SNAEL) of 7.5–38.5 μg/L for drinking water. This should give cause for great environmental concern. Peoples’ health downstream is at stake and so is the ‘health’ of the ecosystem.